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Add new interpolation for most modes and start positioning for P25 and YSF.

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This commit is contained in:
Jonathan Naylor 2017-02-06 21:02:45 +00:00
parent 18ec4bafb6
commit 1bb474dfef
10 changed files with 212 additions and 136 deletions
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71
YSFRX.cpp
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@ -18,7 +18,7 @@
#define WANT_DEBUG
// #define DUMP_SAMPLES
#define DUMP_SAMPLES
#include "Config.h"
#include "Globals.h"
@ -27,8 +27,10 @@
const q15_t SCALING_FACTOR = 18750; // Q15(0.55)
const uint8_t MAX_SYNC_SYMBOLS_ERRS = 2U;
const uint8_t MAX_SYNC_BYTES_ERRS = 3U;
const uint8_t MAX_SYNC_BIT_START_ERRS = 2U;
const uint8_t MAX_SYNC_BIT_RUN_ERRS = 4U;
const uint8_t MAX_SYNC_SYMBOLS_ERRS = 3U;
const uint8_t BIT_MASK_TABLE[] = {0x80U, 0x40U, 0x20U, 0x10U, 0x08U, 0x04U, 0x02U, 0x01U};
@ -44,6 +46,7 @@ m_bitBuffer(),
m_buffer(),
m_bitPtr(0U),
m_dataPtr(0U),
m_startPtr(NOENDPTR),
m_endPtr(NOENDPTR),
m_syncPtr(NOENDPTR),
m_minSyncPtr(NOENDPTR),
@ -70,6 +73,7 @@ void CYSFRX::reset()
m_bitPtr = 0U;
m_maxCorr = 0;
m_averagePtr = 0U;
m_startPtr = NOENDPTR;
m_endPtr = NOENDPTR;
m_syncPtr = NOENDPTR;
m_minSyncPtr = NOENDPTR;
@ -168,10 +172,6 @@ void CYSFRX::processData(q15_t sample)
}
if (m_dataPtr == m_endPtr) {
uint16_t ptr = m_endPtr + YSF_RADIO_SYMBOL_LENGTH + 1U;
if (ptr >= YSF_FRAME_LENGTH_SAMPLES)
ptr -= YSF_FRAME_LENGTH_SAMPLES;
// Only update the centre and threshold if they are from a good sync
if (m_lostCount == MAX_SYNC_FRAMES) {
m_threshold[m_averagePtr] = m_thresholdBest;
@ -204,9 +204,9 @@ void CYSFRX::processData(q15_t sample)
}
uint8_t frame[YSF_FRAME_LENGTH_BYTES + 3U];
samplesToBits(ptr, YSF_FRAME_LENGTH_SYMBOLS, frame, 8U, m_centreVal, m_thresholdVal);
samplesToBits(m_startPtr, YSF_FRAME_LENGTH_SYMBOLS, frame, 8U, m_centreVal, m_thresholdVal);
#if defined(DUMP_SAMPLES)
writeSync(ptr);
writeSync(m_startPtr);
#endif
// We've not seen a data sync for too long, signal RXLOST and change to RX_NONE
@ -244,16 +244,28 @@ bool CYSFRX::correlateSync()
q15_t max = -16000;
q15_t min = 16000;
uint32_t mask = 0x00080000U;
for (uint8_t i = 0U; i < YSF_SYNC_LENGTH_SYMBOLS; i++, mask >>= 1) {
bool b = (YSF_SYNC_SYMBOLS & mask) == mask;
for (uint8_t i = 0U; i < YSF_SYNC_LENGTH_SYMBOLS; i++) {
q15_t val = m_buffer[ptr];
if (m_buffer[ptr] > max)
max = m_buffer[ptr];
if (m_buffer[ptr] < min)
min = m_buffer[ptr];
if (val > max)
max = val;
if (val < min)
min = val;
corr += b ? -m_buffer[ptr] : m_buffer[ptr];
switch (YSF_SYNC_SYMBOLS_VALUES[i]) {
case +3:
corr -= (val + val + val);
break;
case +1:
corr -= val;
break;
case -1:
corr += val;
break;
default: // -3
corr += (val + val + val);
break;
}
ptr += YSF_RADIO_SYMBOL_LENGTH;
if (ptr >= YSF_FRAME_LENGTH_SAMPLES)
@ -268,26 +280,32 @@ bool CYSFRX::correlateSync()
uint8_t sync[YSF_SYNC_BYTES_LENGTH];
uint16_t ptr = m_dataPtr + YSF_FRAME_LENGTH_SAMPLES - YSF_SYNC_LENGTH_SAMPLES + YSF_RADIO_SYMBOL_LENGTH;
if (ptr >= YSF_FRAME_LENGTH_SAMPLES)
ptr -= YSF_FRAME_LENGTH_SAMPLES;
uint16_t startPtr = m_dataPtr + YSF_FRAME_LENGTH_SAMPLES - YSF_SYNC_LENGTH_SAMPLES + YSF_RADIO_SYMBOL_LENGTH;
if (startPtr >= YSF_FRAME_LENGTH_SAMPLES)
startPtr -= YSF_FRAME_LENGTH_SAMPLES;
if (m_state == YSFRXS_NONE)
samplesToBits(ptr, YSF_SYNC_LENGTH_SYMBOLS, sync, 0U, centre, threshold);
else
samplesToBits(ptr, YSF_SYNC_LENGTH_SYMBOLS, sync, 0U, m_centreVal, m_thresholdVal);
uint8_t maxErrs;
if (m_state == YSFRXS_NONE) {
samplesToBits(startPtr, YSF_SYNC_LENGTH_SYMBOLS, sync, 0U, centre, threshold);
maxErrs = MAX_SYNC_BIT_START_ERRS;
} else {
samplesToBits(startPtr, YSF_SYNC_LENGTH_SYMBOLS, sync, 0U, m_centreVal, m_thresholdVal);
maxErrs = MAX_SYNC_BIT_RUN_ERRS;
}
uint8_t errs = 0U;
for (uint8_t i = 0U; i < YSF_SYNC_BYTES_LENGTH; i++)
errs += countBits8(sync[i] ^ YSF_SYNC_BYTES[i]);
if (errs <= MAX_SYNC_BYTES_ERRS) {
if (errs <= maxErrs) {
m_maxCorr = corr;
m_thresholdBest = threshold;
m_centreBest = centre;
m_lostCount = MAX_SYNC_FRAMES;
m_syncPtr = m_dataPtr;
m_startPtr = startPtr;
m_endPtr = m_dataPtr + YSF_FRAME_LENGTH_SAMPLES - YSF_SYNC_LENGTH_SAMPLES - 1U;
if (m_endPtr >= YSF_FRAME_LENGTH_SAMPLES)
m_endPtr -= YSF_FRAME_LENGTH_SAMPLES;
@ -360,6 +378,9 @@ void CYSFRX::writeSync(uint16_t start)
q15_t sync[YSF_SYNC_LENGTH_SYMBOLS];
for (uint16_t i = 0U; i < YSF_SYNC_LENGTH_SYMBOLS; i++) {
if (i == (YSF_SYNC_LENGTH_SYMBOLS - 1U))
DEBUG3("YSFRX: sync/start", m_syncPtr, start);
sync[i] = m_buffer[start];
start += YSF_RADIO_SYMBOL_LENGTH;